2011 End-of-the-Year Card
Hypotrochoids are the types of patterns that are producted by Spirographs. A computer program generates a unique design for each card by choosing random values for the constants of the hypotrochoid equation. The resulting curves are drawn using a pen plotter.
Envelope and unfolded cards:
Stack of finished cards:
The plotter in action:
The hypotrochoid pattern was generated by a custom Python script. The paths were cut and culled using a combination of Inkscape and Illustrator. (Neither tool works well enough to do the job on its own.) The resulting file is converted to HPGL and sent to an HP 7475A plotter.
The typeface used for the card and envelope is Sentinel. The card is drawn using Rapidograph pens on Xerox Digital Color Elite Silk 110lb paper. The envelopes are laser printed on French Paper Company Newsprint Aged Dur-O-Tone.